Distractor heterogeneity effects in visual search are mediated by "segmentability"
Increased distractor heterogeneity complicates visual search, but only when the set of distractors has high dissimilarity. However, if a gap between those dissimilar distractors in the feature space is filled with numerous intermediate feature values, it paradoxically improves the salience of a target singleton despite increased distractor heterogeneity. To explain this paradox we suggested that the distractor heterogeneity effect is mediated by "segmentability". This predicts different heterogeneity effects on singleton search depending on the smoothness of transition between neighboring features.